Becoming a father changes you - in your body, your emotions, your relationships and the way you think about yourself. Many dads experience this transition as exhilarating, challenging and deeply meaningful. Yet the world around them still too often overlooks what fathers go through in the antenatal and postnatal period - and that gap matters for babies and their dads. 

In a recent article for Early Childhood Matters, Dr Lee Gettler explores how fatherhood isn’t just a social role - it’s a biological one too. His research shows that many men experience shifts in hormones like testosterone and oxytocin as they move into active caregiving.  

Biological changes: It’s not just in your head 

When many men become fathers, their testosterone drops - in some studies, by more than 20-25% after the baby’s birth.  

This biological shift isn’t a loss of “manliness” - far from it. Lower testosterone appears linked with greater caregiving motivation and sensitivity. Fathers who spend more time with their infants - reading, feeding, playing - tend to show lower testosterone than less involved dads.  

At the same time, oxytocin, a hormone associated with bonding and empathy, surges when dads hold their newborns and during early caregiving interactions, and spikes when dads play with their children. 

This hormonal choreography is nature’s way of helping dads adjust to the demands of caregiving - strengthening emotional attunement, patience and responsiveness during a time of intense relational learning. 

Emotional & psychological shifts in fatherhood

Hormones are only part of the story. Becoming a dad also brings emotional upheaval. Many fathers describe waves of overwhelming love, fatigue, anxiety, pride and worry all at once - often without a clear roadmap for what’s “normal.” This mix can boost motivation and meaning, but it can also push men toward stress, self-doubt and mental health challenges. 

Research and lived accounts consistently show: 

• Fathers often feel under-seen or under-supported, even though they are deeply involved - a survey found a majority of dads feel they shoulder far more parenting duties than they’re recognised for.  

• Paternal mental health struggles are real - depressive symptoms, anxiety and stress affect a significant number of new fathers, yet they’re far less likely to be screened or offered support than mothers.  

• Many dads struggle to find a coherent identity as a dad, especially when social expectations and services are not designed with them in mind.  

The ripple effect on families 

When fathers are engaged, supported and emotionally present, the benefits are wide-ranging: 

• Children whose fathers are involved show better cognitive, emotional and social development.  

• Partners often feel more supported and share caregiving more equitably - strengthening the couple relationship. 

• Fathers report higher satisfaction, purpose and connection with family life. 

But when fathers feel invisible or unsupported, the risks extend beyond individual distress - they can affect family dynamics, partner wellbeing and crucial child outcomes too. 

So what can perinatal professionals and Dad Matters do to help new dads? 

At Dad Matters, we believe the transition to fatherhood should be met with knowledge, empathy, connection and peer support. Here are practical ways we - and perinatal professionals more broadly - can help: 

1. Prepare dads earlier 

• Include fathers in antenatal education - not as an optional add-on but as essential participants. 

• Offer sessions on hormonal changes, bonding, the variability of fathering styles and realistic expectations about sleep, intimacy and emotional changes. 

2. Normalise emotional change 

• Create spaces where dads can talk candidly about stress, identity shifts and mental health without stigma, but be specific. 

• Normalising the biology of fatherhood (e.g., hormonal shifts) helps dads rethink narratives around masculinity and caregiving.  

3. Targeted support pathways 

• Advocate for routine mental health screening for fathers during pregnancy and postpartum. 

• Embed father-focused follow-ups in community and health services - whether that’s peer support, counselling, or social groups. 

4. Community and connection 

• Build dad-specific networks where men can share experiences, tips and reassurance - not just parenting  essentials, but lived realities. 

• Partner with organisations, like Home-Start, to bridge gaps between formal healthcare and community support. 

5. Cultural shift 

• Challenge outdated ideas about ‘breadwinner’ roles and encourage inclusive narratives of fathering - ones where caregiving, vulnerability and strength co-exist. 

Becoming a dad changes you - it shapes your brain, your hormones, your relationships and your purpose.  

These changes are powerful and adaptive, but they also come with real challenges that deserve recognition and support.